Unless otherwise indicated herein, the description provided in this section is not itself prior art to the claims and is not admitted to be prior art by inclusion in this section.
Various types of hearing prostheses provide people with different types of hearing loss with the ability to perceive sound. Hearing loss may be conductive, sensorineural, or some combination of both conductive and sensorineural. Conductive hearing loss typically results from a dysfunction in any of the mechanisms that ordinarily conduct sound waves through the outer ear, the eardrum, or the bones of the middle ear. Sensorineural hearing loss typically results from a dysfunction in the inner ear, including the cochlea where sound vibrations are converted into neural signals, or any other part of the ear, auditory nerve, or brain that may process the neural signals.
People with some forms of conductive hearing loss may benefit from hearing prostheses such as hearing aids or electromechanical hearing devices. A hearing aid, for instance, typically includes at least one small microphone to receive sound, an amplifier to amplify certain portions of the detected sound, and a small speaker to transmit the amplified sounds into the person's ear. An electromechanical hearing device, on the other hand, typically includes at least one small microphone to receive sound and a mechanism that delivers a mechanical force to a bone (e.g., the recipient's skull, or middle-ear bone such as the stapes) or to a prosthetic (e.g., a prosthetic stapes implanted in the recipient's middle ear), thereby causing vibrations in cochlear fluid.
Further, people with certain forms of sensorineural hearing loss may benefit from hearing prostheses such as cochlear implants and/or auditory brainstem implants. Cochlear implants, for example, include at least one microphone to receive sound, a unit to convert the sound to a series of electrical stimulation signals, and an array of electrodes to deliver the stimulation signals to the implant recipient's cochlea so as to help the recipient perceive sound. Auditory brainstem implants use technology similar to cochlear implants, but instead of applying electrical stimulation to a person's cochlea, they apply electrical stimulation directly to a person's brain stem, bypassing the cochlea altogether, still helping the recipient perceive sound.
In addition, some people may benefit from hybrid hearing prostheses, which combine one or more characteristics of the acoustic hearing aids, vibration-based hearing prostheses, cochlear implants, and auditory brainstem implants to enable the person to perceive sound.
A hearing prosthesis could include an external unit that performs at least some processing functions and an internal stimulation unit that at least delivers a stimulus to a body part in an auditory pathway of the recipient. The auditory pathway includes a cochlea, an auditory nerve, a region of the recipient's brain, or any other body part that contributes to the perception of sound. In the case of a totally implantable medical device, the stimulation unit includes both processing and stimulation components, though an external unit could still perform some processing functions when communicatively coupled or connected to the stimulation unit.
A recipient of the hearing prosthesis may wear the external unit of the hearing prosthesis on the recipient's body, typically at a location near one of the recipient's ears. The external unit could be capable of being physically attached to the recipient, or the external unit could be attached to the recipient by magnetically coupling the external unit and the stimulation unit.
A hearing prosthesis could have a variety of settings that control the generation of stimuli provided to a user based on detected sounds. Such settings can include settings of a filter bank used to filter the received audio, a gain applied to the received audio, a mapping between frequency ranges of received audio and stimulation electrodes, or other settings. A hearing prosthesis can include multiple sets of such settings, where each set is associated with a respective audio environment. For example, a first set of settings could be associated with an audio environment that includes speech in noise (e.g., speech from a waiter in a crowded restaurant) and a second set of settings could be associated with an audio environment that includes music (e.g., music produced by a radio). The first set of settings could include filter bank settings specified to help a user understand speech based on stimuli provided by the hearing prosthesis, and the second set of settings could include filter bank settings specified to help a user perceive the tone or other properties of music based on stimuli provided by the hearing prosthesis. The hearing prosthesis could be configured to identify an audio environment, based on detected sound, and to provide stimuli to a user using a set of settings associated with the identified audio environment.